US3756073A - Non-contact tonometer - Google Patents

Non-contact tonometer Download PDF

Info

Publication number
US3756073A
US3756073A US00202423A US3756073DA US3756073A US 3756073 A US3756073 A US 3756073A US 00202423 A US00202423 A US 00202423A US 3756073D A US3756073D A US 3756073DA US 3756073 A US3756073 A US 3756073A
Authority
US
United States
Prior art keywords
alignment
axis
along
image
projection
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00202423A
Other languages
English (en)
Inventor
R Lavallee
B Grolman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CAMBRIDGE INSTRUMENTS Inc A CORP OF
American Optical Corp
Leica Microsystems Inc
Original Assignee
American Optical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by American Optical Corp filed Critical American Optical Corp
Application granted granted Critical
Publication of US3756073A publication Critical patent/US3756073A/en
Assigned to WARNER LAMBERT TECHNOLOGIES, INC., A CORP OF TX. reassignment WARNER LAMBERT TECHNOLOGIES, INC., A CORP OF TX. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: WARNER LAMBERT COMPANY
Assigned to WARNER LAMBERT COMPANY, A CORP. OF DEL. reassignment WARNER LAMBERT COMPANY, A CORP. OF DEL. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: AMERICAN OPTICAL CORPORATION,
Assigned to CAMBRIDGE INSTRUMENTS INC., A CORP. OF DE reassignment CAMBRIDGE INSTRUMENTS INC., A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: WARNER LAMBERT TECHNOLOGIES, INC., A TX CORP.
Assigned to CAMBRIDGE INSTRUMENTS INC., A DE CORP. reassignment CAMBRIDGE INSTRUMENTS INC., A DE CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: WARNER LAMBERT TECHNOLOGIES, INC.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/16—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for measuring intraocular pressure, e.g. tonometers
    • A61B3/165—Non-contacting tonometers

Definitions

  • ABSTRACT An alignment system for a non-contact tonometer in 52 us. c1. 73/80, 356/152 which the pneumatic and corneal monitoring y m [51] Int. Cl A611) 3/16 are aligned relative to h rne such that a target [58] Field of Search 73/80; 356/152, 153 image reflected fr the rn a i superimposed on an aiming reticle and on a photocell.
  • the non-contact tonometer to which this invention relates operates by discharging an air pulse of a known force-time relationship onto the cornea of a patient.
  • the resulting deformation of the cornea from convexity through applanation to concavity, and return, is observed as a function of time and thus correlated to intraocular pressure.
  • the positioning and alignment of the apparatus relative to the subject cornea is critical.
  • Another object is to provide such a tonometer and alignment provision with a verification feature which permits operation of the tonometer only when proper alignment is achieved.
  • the present invention is practiced in one form by a non-contact tonometer having an optical spherometer type of alignment system for positioning the apparatus at a known distance from and normal to a corneal surface.
  • a target image reflected from the spherical corneal surface is viewed by an observer and the apparatus aligned such that the image coincides with an aiming reticle.
  • the image, when thus aligned, is also detected by a photocell whereupon the operating trigger circuit for the tonometer is armed.
  • the instrument will only operate when proper alignment is achieved.
  • FIG. 1 is a schematic side view of the pneumatic system of a non-contact tonometer to which this invention relates.
  • FIG. 2 is a schematic plan view of the monitoring system of this tonometer and an undisturbed cornea.
  • FIG. 3 is a view similar to Figure 2 showing the monitoring system and an applanated cornea.
  • FIG. 4 is a schematic plan view of the tonometer alignment verification system of this invention.
  • a non-contact tonometer is generally indicated at 2 and its pneumatic system is depicted here in side view. It essentially includes a rotary solenoid 4, a connecting linkage 6, a piston 8, and a cylinder 10. Piston 8 is disposed with the cylinder 10 and is connected to the actuating solenoid 4 by connecting link 6. Cylinder 10, together with a window 12 and a modified microscope objective M define a pressure chamber 16. The objective 14 defines an axial passage through which an orifice tube 18 extends. This apparatus is shown disposed adjacent to the cornea 20 of a patient. Orifice tube 18 is directed toward the cornea along axis 26. A telescope lens 36, reticle plane 34, and eyepiece 36 are also located along axis 26.
  • the piston 8 accelerates at a controlled rate into the pressure chamber 16 in cylinder Ill).
  • the positive pressure thus generated within chamber .16 is ported through the orifice tube 18 in the direction of the patients cornea 20.
  • this air pulse impinges on a properly oriented cornea 20, it sequentially causes the deformation of the corneal surface through a reduction of curvature, then through an occurrence of applanation, to a slight concavity. Then, with the decay of the force-time envelope, there is progressive restoration of the cornea back through applanation.
  • the objective l4, tube 18, and cornea 20 are shown from a top view as they are situated along axis 26 and as they relate to elements of a monitoring system which includes a transmitter 22 and a telecentric receiver 24.
  • Transmitter 22 directs a collimated beam of light, represented by three incident rays li, 0i, and 2i at cornea 20.,-Refiected rays 1r, Or, and Zr are shown reflecting in various directions from the convex (or non-planar) corneal surface.
  • FIG. 3 is a view of the same elements shown in FIG. 2 except that the cornea 20 in this case is shown at an instantaneous occurrence of applanation as the result of the air pulse discharge through orifice tube 18.
  • the effect of applanation on the monitoring system is shown whereby the collimated incident light rays Ii, 01', and 2i are reflected by the applanated surface as collimated rays and thus the telecentric receiver 24 receives a maximum signal at this instantaneous occurrence. This maximum signal thus indicates the occurrence of applanation.
  • the alignment verification system of this invention is shown in a somewhat schematic plan view.
  • the tonometer 2 with objective 14 and orifice tube 118 is shown positioned adjacent the patients cornea 20 along an alignment axis 26 normal to the corneal surface.
  • Light transmitter 22 and receiver 24 are shown obliquely situated at equal angles on opposite sides of the alignment axis 26.
  • a projection beam splitter or beam deflector 28, telescope lens 30, detection beam splitter 32, aiming circle reticle 34, and eyepiece 36 are disposed in optical alignment with objective 14 along the alignment axis 26.
  • a target projection system includes a light source 38, collecting lens 40, light transmitting surface 42 on which is placed a fixation target 44, a beam splitter 46, mirror 48, and collimator lens 50, all disposed along a projection axis 52 which joins alignment axis 26 at the projection beam splitter 28.
  • a light emitting diode 54 is positioned behind beam splitter 46 such that light from the diode 54 (preferably of approximately 900 nm wavelength), which is in the infra-red or invisible range of the light spectrum, is transmitted through the beam splitter 46 and along the projection axis 52.
  • Detection beam splitter 32 partially reflects light from the alignment axis 26 to an alignment detector or photodetector 56.
  • the fixation target 44 is preferably a red spot on a difiuse white background 42.
  • the projection system projects an image of target 44, through objective 14, to the image plane 58 of objective 14.
  • the tonometer 2 is moved so that the image plane 58 is coincident with the center of curvature of the cornea 20, a corneal virtual or mirror image of the target is re-imaged by objective 14 and telescope 30 in the plane of circle reticle 34.
  • This image at the plane of reticle 34 is then viewed through eyepiece 36 by the operator, represented at 60.
  • the alignment axis 26 is normal to the local corneal surface, the image of target 44 is centered within the aiming circle reticle 34.
  • the corneal surface under observation is limited to a desired small portion of the entire corneal surface. it is insured that the alignment is with respect to the desired portion by directing the subject eye to fixate target 44, which is viewed by the patient along alignment axis 26 (and projection axis 52). The patient views the target 44 at optical infinity through the orifice tube 18.
  • an external fixation light (not shown) is used toward which to direct the sighted eye and thus to direct the sightless eye in a frontal orientation with respect to the instrument.
  • the image of target 44 is projected toward the cornea 20 and reflected therefrom and re-imaged at the center of circle reticle 34 (where it is observed by the operator).
  • Concurrently 900 nm emission from diode 54 is also projected along axis 52 toward cornea 20 and similarly reflected along axis 26. That is, from the exit side of beam splitter 46, radiations from the target 44 and from diode 54 are coincident along the projection axis 52 and the alignment axis 26.
  • Detection beam splitter 32 directs some of the reflected radiation from both the target 44 and the diode 54 to alignment detector or photodetector 56.
  • Detector 56 is sensitive to the 900 nm radiation from diode 54 and when subjected to such radiation, detector 56 arms the trigger circuit which controls the solenoid 4 and the air pulse discharge of the tonometer.
  • the pupil of the detector 56 is sized so that it functions automatically (in the same sense that the aiming circle reticle is used visually) to permit the tonometer to function only when the alignment satisifies spatial tolerances determined by the diameters of circle reticle 34 and the pupil of the sensing aperture of detector 56.
  • an additional feature of the alignment system includes a five-position turret 62 interposed between collimating lens 50 and beam splitter 28.
  • Turret 62 has five apertures selectively positionable in the projection axis 52 for the transmission of the full beam of projection light as represented in the drawing. ln the centers of four of these apertures, a small (e.g. 3 millimeter diameter) dioptric lens 64 is situated, each of a different power.
  • the dioptric lens 64 is small relative to the projection light beam and therefore modifies only its central aperture corresponding to the orifice in tube 18 through which the patient fixates the target.
  • Selective positioning of turret 62 about an axis of rotation 66 provides the target 44.
  • the plane parallel window 68 upon which the correcting lens 64 is mounted does not alter the aperture of objective 14 which focuses the target 44 at image plane 58.
  • a non-contact tonometer having a pneumatic system in which a fluid pulse is directed along a pneumatic axis and at a patients corneal surface, and a monitoring system in which the effect of said pulse on said surface is determined, said pneumatic system and said monitoring system each including a control means, said tonometer being characterized by an alignment system disposed relative to an alignment axis coincident with said pneumatic axis, said alignment system including:
  • projection means to project a visible target image through said objective lens along said alignment axis toward the focal plane thereof and toward said corneal surface, said target image being reflected by said corneal surface along said alignment axis to form a visible reflected image at said observation means
  • a source of invisible alignment radiation and means to project an image of the source along said alignment axis toward said corneal surface, said source image being reflected by said corneal surface along said alignment axis toward said observation means,
  • a beam divider disposed along said alignment axis between said objective and said observation means to direct the source image to a conjugate image plane
  • a detector sensitive to said invisible alignment radiation at said conjugate image plane, said detector operatively connected to the control means of said pneumatic system and responsive to a conjugate reflected source image coincident thereon to actuate the control means of said pneumatic system.
  • said projection means including a visible light source, a target, and a beam deflector disposed along a projection axis, said projection axis joining said alignment axis at said beam deflector, said visible light source and said target effective to project said target image along said projection axis.
  • said projection means further including a battery of dioptric lenses selectively positionable along said projection axis to accommodate for refractive error in the eye of a patient enabling the patient to better fixate said target image.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Medical Informatics (AREA)
  • Biophysics (AREA)
  • Ophthalmology & Optometry (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Eye Examination Apparatus (AREA)
US00202423A 1971-11-26 1971-11-26 Non-contact tonometer Expired - Lifetime US3756073A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US20242371A 1971-11-26 1971-11-26

Publications (1)

Publication Number Publication Date
US3756073A true US3756073A (en) 1973-09-04

Family

ID=22749814

Family Applications (1)

Application Number Title Priority Date Filing Date
US00202423A Expired - Lifetime US3756073A (en) 1971-11-26 1971-11-26 Non-contact tonometer

Country Status (8)

Country Link
US (1) US3756073A (enrdf_load_stackoverflow)
JP (1) JPS566772B2 (enrdf_load_stackoverflow)
AT (1) AT328064B (enrdf_load_stackoverflow)
CA (1) CA965257A (enrdf_load_stackoverflow)
DE (1) DE2252313C2 (enrdf_load_stackoverflow)
FR (1) FR2162911A5 (enrdf_load_stackoverflow)
GB (1) GB1348179A (enrdf_load_stackoverflow)
IT (1) IT966784B (enrdf_load_stackoverflow)

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2741381A1 (de) * 1976-10-16 1978-04-20 Canon Kk Verfahren und vorrichtung zur ermittlung des abstands zwischen einem instrument zur untersuchung eines auges und dem auge
DE2828405A1 (de) * 1977-06-29 1979-01-11 Canon Kk Augenuntersuchungseinrichtung
US4159019A (en) * 1974-10-31 1979-06-26 Farias Natalicio L De Instrument for use in taking ocular tension measurements by the tonometric method of ocular depressions
DE3138122A1 (de) * 1980-09-24 1982-04-22 Tokyo Kogaku Kikai K.K., Tokyo Augenuntersuchungsinstrument mit einer einrichtung zum automatischen anzeigen der richtigen stellung des zu untersuchenden auges
DE3124192A1 (de) * 1981-06-19 1983-01-13 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München Verfahren und anordnung zur positionierung einer vorrichtung zur augenuntersuchung
US4386611A (en) * 1980-06-02 1983-06-07 Warner Lambert Technologies, Inc. Tonometer with improved fluid discharged tube
US4412543A (en) * 1981-04-09 1983-11-01 Xanar, Inc. Apparatus for determining the concentration of a fluorescent material in an eye
US4523597A (en) * 1982-12-29 1985-06-18 Minolta Camera Kabushiki Kaisha Apparatus and method for measuring the intraocular pressure of an eyeball and auxiliary device for using therewith
GB2175412A (en) * 1985-05-23 1986-11-26 Pa Consulting Services Tonometer
US4665923A (en) * 1984-11-27 1987-05-19 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
EP0164730A3 (en) * 1984-06-12 1987-09-09 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4705045A (en) * 1985-02-26 1987-11-10 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4817620A (en) * 1986-09-06 1989-04-04 Tokyo Kogaku Kikai Kabushiki Kaisha Noncontact type tonometer
US4825873A (en) * 1986-07-26 1989-05-02 Canon Kabushiki Kaisha Non-contact eye pressure meter
US4872460A (en) * 1986-08-21 1989-10-10 Tokyo Kogaku Kikai Kabushiki Kaisha Noncontact type tonometer
DE3913311A1 (de) * 1988-04-21 1989-11-02 Topcon Corp Beruehrungsloser druckmesser fuer intraokularen druck
US4944303A (en) * 1986-12-27 1990-07-31 Topcon Corporation Noncontact type tonometer
US4947849A (en) * 1984-06-12 1990-08-14 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4995393A (en) * 1988-04-08 1991-02-26 Kabushiki Kaisha Topcon Alignment apparatus of noncontact type tonometer
US5000181A (en) * 1988-04-15 1991-03-19 Kabushiki Kaisha Topcon Noncontact type tonometer
US5031623A (en) * 1988-05-31 1991-07-16 Canon Kabushiki Kaisha Non-contact tonometer
US5076274A (en) * 1987-02-18 1991-12-31 Canon Kabushiki Kaisha Non-contact tonometer
US5101826A (en) * 1988-05-11 1992-04-07 Kabushiki Kaisha Topcon Noncontact type tonometer
US5203331A (en) * 1989-07-17 1993-04-20 Haag-Streit Ag Applanation tonometer
US5396888A (en) * 1991-10-10 1995-03-14 Massie Research Laboratories, Inc. Non-contact tonometer and method using ultrasonic beam
US5474066A (en) * 1994-01-31 1995-12-12 Leica Inc. Non-contact tonometer
US5546941A (en) * 1994-10-28 1996-08-20 Cds Technologies, L.L.C. Patient operated tonometers
US5810005A (en) * 1993-08-04 1998-09-22 Dublin, Jr.; Wilbur L. Apparatus and method for monitoring intraocular and blood pressure by non-contact contour measurement
EP1147738A1 (en) 2000-04-20 2001-10-24 Leica Microsystems Inc. , Ophthalmic Instruments Division Non-contact tonometry method
US6361495B1 (en) 2000-02-07 2002-03-26 Leica Microsystems Inc. Hand-held non-contact tonometer
EP1308125A2 (en) 2001-11-06 2003-05-07 Leica Microsystems Inc. Alignment system for an ophthalmic instrument
US6749302B2 (en) 2001-11-06 2004-06-15 Reichert, Inc. Afocal position detection system and ophthalmic instrument employing said system
US20050001981A1 (en) * 2003-07-03 2005-01-06 Anderson Daryl E. Ophthalmic apparatus and method for administering agents to the eye
US6945650B2 (en) 2001-11-06 2005-09-20 Reichert, Inc. Alignment system for hand-held ophthalmic device
WO2014202840A1 (en) * 2013-06-20 2014-12-24 Icare Finland Oy An optometric instrument with alignment means and method for aligning an optometric instrument
US20180116512A1 (en) * 2014-07-17 2018-05-03 I Sonic Medical Corporation, S.A.S. Measurement of ocular parameters using vibrations induced in the eye
US11219367B2 (en) 2020-01-30 2022-01-11 Reichert, Inc. Positioning system for ophthalmic instrument

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53148195A (en) * 1977-05-30 1978-12-23 Canon Kk Method of taking eyeeground camera
JPS58116336A (ja) * 1981-12-28 1983-07-11 キヤノン株式会社 眼科機器の位置合わせ装置
JPS6083642A (ja) * 1983-10-14 1985-05-11 キヤノン株式会社 眼圧測定装置
GB8618084D0 (en) * 1986-07-24 1986-09-03 Nowinski S Measuring physical properties of liquids
JPH0624519B2 (ja) * 1986-08-21 1994-04-06 株式会社トプコン 非接触式眼圧計
US4991584A (en) * 1986-10-25 1991-02-12 Canon Kabushiki Kaisha Ophthalmic examining apparatus and method capable of examining glaucoma
CN110567973B (zh) * 2019-09-27 2022-07-05 济南大学 一种基于图像采集的活塞检测平台及方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2352179A (en) * 1944-06-27 Lens centering device
US3471237A (en) * 1966-02-15 1969-10-07 Barnes Eng Co Method of alignment of concave parabolic reflective optics
US3538754A (en) * 1969-01-15 1970-11-10 American Optical Corp Method for measuring intraocular pressure
US3552857A (en) * 1965-04-24 1971-01-05 Leitz Ernst Gmbh Optical device for the determination of the spacing of an object and its angular deviation relative to an initial position
US3585849A (en) * 1968-10-09 1971-06-22 American Optical Corp Method and apparatus for measuring intraocular pressure
US3603688A (en) * 1967-11-08 1971-09-07 Perkin Elmer Corp Alignment apparatus

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2352179A (en) * 1944-06-27 Lens centering device
US3552857A (en) * 1965-04-24 1971-01-05 Leitz Ernst Gmbh Optical device for the determination of the spacing of an object and its angular deviation relative to an initial position
US3471237A (en) * 1966-02-15 1969-10-07 Barnes Eng Co Method of alignment of concave parabolic reflective optics
US3603688A (en) * 1967-11-08 1971-09-07 Perkin Elmer Corp Alignment apparatus
US3585849A (en) * 1968-10-09 1971-06-22 American Optical Corp Method and apparatus for measuring intraocular pressure
US3538754A (en) * 1969-01-15 1970-11-10 American Optical Corp Method for measuring intraocular pressure

Cited By (53)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4159019A (en) * 1974-10-31 1979-06-26 Farias Natalicio L De Instrument for use in taking ocular tension measurements by the tonometric method of ocular depressions
DE2741381A1 (de) * 1976-10-16 1978-04-20 Canon Kk Verfahren und vorrichtung zur ermittlung des abstands zwischen einem instrument zur untersuchung eines auges und dem auge
DE2828405A1 (de) * 1977-06-29 1979-01-11 Canon Kk Augenuntersuchungseinrichtung
US4386611A (en) * 1980-06-02 1983-06-07 Warner Lambert Technologies, Inc. Tonometer with improved fluid discharged tube
DE3138122A1 (de) * 1980-09-24 1982-04-22 Tokyo Kogaku Kikai K.K., Tokyo Augenuntersuchungsinstrument mit einer einrichtung zum automatischen anzeigen der richtigen stellung des zu untersuchenden auges
US4412543A (en) * 1981-04-09 1983-11-01 Xanar, Inc. Apparatus for determining the concentration of a fluorescent material in an eye
DE3124192A1 (de) * 1981-06-19 1983-01-13 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München Verfahren und anordnung zur positionierung einer vorrichtung zur augenuntersuchung
US4523597A (en) * 1982-12-29 1985-06-18 Minolta Camera Kabushiki Kaisha Apparatus and method for measuring the intraocular pressure of an eyeball and auxiliary device for using therewith
US5002056A (en) * 1984-06-12 1991-03-26 Tokyo Kabushiki Kikai Kabushiki Kaisha Non-contact type tonometer
EP0164730A3 (en) * 1984-06-12 1987-09-09 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4947849A (en) * 1984-06-12 1990-08-14 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
EP0183621A3 (en) * 1984-11-27 1988-04-27 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4665923A (en) * 1984-11-27 1987-05-19 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4705045A (en) * 1985-02-26 1987-11-10 Tokyo Kogaku Kikai Kabushiki Kaisha Non-contact type tonometer
US4724843A (en) * 1985-05-23 1988-02-16 Keeler Limited Tonometer
GB2175412B (en) * 1985-05-23 1989-06-28 Pa Consulting Services Eye testing method and apparatus
EP0209966A1 (en) * 1985-05-23 1987-01-28 Keeler Limited System for measuring intraocular pressure
GB2175412A (en) * 1985-05-23 1986-11-26 Pa Consulting Services Tonometer
US4825873A (en) * 1986-07-26 1989-05-02 Canon Kabushiki Kaisha Non-contact eye pressure meter
US4872460A (en) * 1986-08-21 1989-10-10 Tokyo Kogaku Kikai Kabushiki Kaisha Noncontact type tonometer
US4817620A (en) * 1986-09-06 1989-04-04 Tokyo Kogaku Kikai Kabushiki Kaisha Noncontact type tonometer
US4944303A (en) * 1986-12-27 1990-07-31 Topcon Corporation Noncontact type tonometer
US5076274A (en) * 1987-02-18 1991-12-31 Canon Kabushiki Kaisha Non-contact tonometer
US4995393A (en) * 1988-04-08 1991-02-26 Kabushiki Kaisha Topcon Alignment apparatus of noncontact type tonometer
US5000181A (en) * 1988-04-15 1991-03-19 Kabushiki Kaisha Topcon Noncontact type tonometer
DE3913311A1 (de) * 1988-04-21 1989-11-02 Topcon Corp Beruehrungsloser druckmesser fuer intraokularen druck
US5101826A (en) * 1988-05-11 1992-04-07 Kabushiki Kaisha Topcon Noncontact type tonometer
US5031623A (en) * 1988-05-31 1991-07-16 Canon Kabushiki Kaisha Non-contact tonometer
US5203331A (en) * 1989-07-17 1993-04-20 Haag-Streit Ag Applanation tonometer
US5396888A (en) * 1991-10-10 1995-03-14 Massie Research Laboratories, Inc. Non-contact tonometer and method using ultrasonic beam
US5810005A (en) * 1993-08-04 1998-09-22 Dublin, Jr.; Wilbur L. Apparatus and method for monitoring intraocular and blood pressure by non-contact contour measurement
US6110110A (en) * 1993-08-04 2000-08-29 Dublin, Jr.; Wilbur Leslie Apparatus and method for monitoring intraocular and blood pressure by non-contact contour measurement
US5474066A (en) * 1994-01-31 1995-12-12 Leica Inc. Non-contact tonometer
US5546941A (en) * 1994-10-28 1996-08-20 Cds Technologies, L.L.C. Patient operated tonometers
US6361495B1 (en) 2000-02-07 2002-03-26 Leica Microsystems Inc. Hand-held non-contact tonometer
EP1419729A1 (en) * 2000-02-07 2004-05-19 Leica Microsystems Inc. , Ophthalmic Instruments Division Alignment guidance system
EP1147738A1 (en) 2000-04-20 2001-10-24 Leica Microsystems Inc. , Ophthalmic Instruments Division Non-contact tonometry method
US6419631B1 (en) * 2000-04-20 2002-07-16 Leica Microsystems Inc. Non-contact tonometry method
US6669340B2 (en) 2001-11-06 2003-12-30 Reichert, Inc. Alignment system for an ophthalmic instrument
EP1308125A2 (en) 2001-11-06 2003-05-07 Leica Microsystems Inc. Alignment system for an ophthalmic instrument
US6749302B2 (en) 2001-11-06 2004-06-15 Reichert, Inc. Afocal position detection system and ophthalmic instrument employing said system
EP1308125A3 (en) * 2001-11-06 2003-09-17 Leica Microsystems Inc. Alignment system for an ophthalmic instrument
US6945650B2 (en) 2001-11-06 2005-09-20 Reichert, Inc. Alignment system for hand-held ophthalmic device
DE10315262B4 (de) * 2002-04-05 2010-01-21 Reichert, Inc. Ausrichtungssytem für ein handgeführtes ophtalmologisches Gerät
US8128606B2 (en) * 2003-07-03 2012-03-06 Hewlett-Packard Development Company, L.P. Ophthalmic apparatus and method for administering agents to the eye
US20050001981A1 (en) * 2003-07-03 2005-01-06 Anderson Daryl E. Ophthalmic apparatus and method for administering agents to the eye
WO2014202840A1 (en) * 2013-06-20 2014-12-24 Icare Finland Oy An optometric instrument with alignment means and method for aligning an optometric instrument
CN105705077A (zh) * 2013-06-20 2016-06-22 伊卡尔芬兰有限公司 带有对准机构的验光设备和用于对准验光设备的方法
AU2014283086B2 (en) * 2013-06-20 2018-07-19 Icare Finland Oy An optometric instrument with alignment means and method for aligning an optometric instrument
US10058245B2 (en) 2013-06-20 2018-08-28 Icare Finland Oy Optometric instrument with alignment means and method for aligning an optometric instrument
US20180116512A1 (en) * 2014-07-17 2018-05-03 I Sonic Medical Corporation, S.A.S. Measurement of ocular parameters using vibrations induced in the eye
US11006828B2 (en) * 2014-07-17 2021-05-18 1 Sonic Medical Corporation, S.A.S. Measurement of ocular parameters using vibrations induced in the eye
US11219367B2 (en) 2020-01-30 2022-01-11 Reichert, Inc. Positioning system for ophthalmic instrument

Also Published As

Publication number Publication date
DE2252313A1 (de) 1973-05-30
CA965257A (en) 1975-04-01
GB1348179A (en) 1974-03-13
FR2162911A5 (enrdf_load_stackoverflow) 1973-07-20
ATA880772A (de) 1975-05-15
JPS4863592A (enrdf_load_stackoverflow) 1973-09-04
AT328064B (de) 1976-03-10
IT966784B (it) 1974-02-20
DE2252313C2 (de) 1982-11-18
JPS566772B2 (enrdf_load_stackoverflow) 1981-02-13

Similar Documents

Publication Publication Date Title
US3756073A (en) Non-contact tonometer
US3832890A (en) Non-contact tonometer corneal monitoring system
US4944303A (en) Noncontact type tonometer
US4665923A (en) Non-contact type tonometer
US4251139A (en) Eye examining instrument
GB1226709A (enrdf_load_stackoverflow)
US4705045A (en) Non-contact type tonometer
US6131574A (en) Ophthalmological apparatus
JPH0354574B2 (enrdf_load_stackoverflow)
JPS6365333B2 (enrdf_load_stackoverflow)
JPS6324383B2 (enrdf_load_stackoverflow)
JPH01265937A (ja) 眼科器械
JPS6116729A (ja) 眼圧測定装置
US5101826A (en) Noncontact type tonometer
US5000181A (en) Noncontact type tonometer
JPH0554337B2 (enrdf_load_stackoverflow)
JPH03176023A (ja) 眼科装置
JP3571102B2 (ja) 眼科装置
JPH0430296B2 (enrdf_load_stackoverflow)
JPH0554338B2 (enrdf_load_stackoverflow)
JPH0357204Y2 (enrdf_load_stackoverflow)
JPS6021738A (ja) 眼科用測定装置
JP3156859B2 (ja) 非接触式眼圧計
JP2736649B2 (ja) 非接触眼圧計
JP3046600B2 (ja) 眼科装置

Legal Events

Date Code Title Description
AS Assignment

Owner name: WARNER LAMBERT COMPANY, 201 TABOR ROAD, MORRIS PLA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:AMERICAN OPTICAL CORPORATION,;REEL/FRAME:004034/0681

Effective date: 19820513

Owner name: WARNER LAMBERT TECHNOLOGIES, INC.; 6373 STEMMONS F

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WARNER LAMBERT COMPANY;REEL/FRAME:004034/0700

Effective date: 19820514

STCF Information on status: patent grant

Free format text: PATENTED FILE - (OLD CASE ADDED FOR FILE TRACKING PURPOSES)

AS Assignment

Owner name: CAMBRIDGE INSTRUMENTS INC., A CORP. OF DE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WARNER LAMBERT TECHNOLOGIES, INC., A TX CORP.;REEL/FRAME:004718/0740

Effective date: 19870519

AS Assignment

Owner name: CAMBRIDGE INSTRUMENTS INC., A DE CORP.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WARNER LAMBERT TECHNOLOGIES, INC.;REEL/FRAME:004893/0097

Effective date: 19880407